The somaclone, C39, derived by tissue culture from the obligate apomict Paspalum dilatatum cv Raki (2n=50), had 50 chromosomes and a karyotype apparently identical to Raki.SC2 seedlings of C39 showed a high degree of ...The somaclone, C39, derived by tissue culture from the obligate apomict Paspalum dilatatum cv Raki (2n=50), had 50 chromosomes and a karyotype apparently identical to Raki.SC2 seedlings of C39 showed a high degree of phenotypic variation which was of ten associated with increased chromosome numbers, but some of the variant seedlings were karyotypically indistinguishable from Raki or C39. Plants with increased chromosome numbers exhibited a high degree of intraplant chromosome variation (aneusomaty). In one of the SC2seedlings, the chromosome number of root tip cells varied from 58 to 82 and in several other seedlings the range was more than 10. The results suggested that the ability to form seed apomictically was much reduced in C39 and that this plant showed some capacity for sexual reproduction and the resulting seedlings, with a chromosome number of about 70, were genetically unstable. Of 11 SC2 seedlings examined cytolog ically, 6 did not produce any viable seed. Seedlings grown from seed of the remaining 5 plants showed that aneusomaty persisted in the SC3 generation. SC3 seedlings which were phenotypically similar to their maternal parent showed a similar range of chromosome numbers to that parent. Some of the SC3 seedlings exhibited an even wider range of chromosome numbers (e.g.56-136), and these plants were all dwarfs.展开更多
Iterative linear programming methods are proposed for optimum balanced animal diet in this paper. According to ＂wooden bucket theory＂ of the nutritional balance, each nutrient in the feeding standard has equal impor...Iterative linear programming methods are proposed for optimum balanced animal diet in this paper. According to ＂wooden bucket theory＂ of the nutritional balance, each nutrient in the feeding standard has equal importance. It＇s unreasonable to use common goal programming to attach different weighted value to different nutritional parameters. This paper introduces an effective algorithm to deal with this kind of problem. When the permitting cost of livestock ration is given, we can design a ration formula with linear program-this is the first round. Then, according to the differences between the permitting cost and the formula cost gained in the first round, adjust the feeding standard and the feeding raw materials, and conduct the second round of linear programming for ration formula. If there is still a very big difference between the formula cost and the permitting cost, the third round will be taken, and so on. In this iteration course the formula cost gradually approaches the permitting cost. It is the key that the feeding standard and feeding raw materials are modified in each round. This method ensured the nutritive equilibrium with the formulation of least-cost ration. This is an especially important method when the primary goal of the optimization tool is to improve economic and nutritive efficiency.展开更多
文摘The somaclone, C39, derived by tissue culture from the obligate apomict Paspalum dilatatum cv Raki (2n=50), had 50 chromosomes and a karyotype apparently identical to Raki.SC2 seedlings of C39 showed a high degree of phenotypic variation which was of ten associated with increased chromosome numbers, but some of the variant seedlings were karyotypically indistinguishable from Raki or C39. Plants with increased chromosome numbers exhibited a high degree of intraplant chromosome variation (aneusomaty). In one of the SC2seedlings, the chromosome number of root tip cells varied from 58 to 82 and in several other seedlings the range was more than 10. The results suggested that the ability to form seed apomictically was much reduced in C39 and that this plant showed some capacity for sexual reproduction and the resulting seedlings, with a chromosome number of about 70, were genetically unstable. Of 11 SC2 seedlings examined cytolog ically, 6 did not produce any viable seed. Seedlings grown from seed of the remaining 5 plants showed that aneusomaty persisted in the SC3 generation. SC3 seedlings which were phenotypically similar to their maternal parent showed a similar range of chromosome numbers to that parent. Some of the SC3 seedlings exhibited an even wider range of chromosome numbers (e.g.56-136), and these plants were all dwarfs.
文摘Iterative linear programming methods are proposed for optimum balanced animal diet in this paper. According to ＂wooden bucket theory＂ of the nutritional balance, each nutrient in the feeding standard has equal importance. It＇s unreasonable to use common goal programming to attach different weighted value to different nutritional parameters. This paper introduces an effective algorithm to deal with this kind of problem. When the permitting cost of livestock ration is given, we can design a ration formula with linear program-this is the first round. Then, according to the differences between the permitting cost and the formula cost gained in the first round, adjust the feeding standard and the feeding raw materials, and conduct the second round of linear programming for ration formula. If there is still a very big difference between the formula cost and the permitting cost, the third round will be taken, and so on. In this iteration course the formula cost gradually approaches the permitting cost. It is the key that the feeding standard and feeding raw materials are modified in each round. This method ensured the nutritive equilibrium with the formulation of least-cost ration. This is an especially important method when the primary goal of the optimization tool is to improve economic and nutritive efficiency.
